Set the tonal range with a mask

When you set black and white points in the Basic tab to get a full range of tones, a neat alternative to using the O and U clipping indicators is to use a mask view. To do this, hold Alt while moving the Blacks or Whites slider. This gives a mask view of the scene and reveals where the shadows or highlights lose detail. It performs the same task as the blue or red overlays created by the clipping warnings, but provides a view devoid of ‘ant’ distractions. Both methods work, but over time, you’ll find you prefer one or the other for setting your points.